{
  // 🎯需求；声明一个数组，成员的所有值数组，字符串，布尔型
  type CustomArray = (number | string | boolean)[];
  let arr1: CustomArray = [1, "a", 3, "b", true];
  let arr2: CustomArray = ["x", "y", 6, 7, false];
  // 🎯基础写法
  type CustomArra = number | string | boolean;
  let arr3: CustomArray = [1, "a", 3, "b", true];
  let arr4: CustomArray = ["x", "y", 6, 7, false];
  // 🎈其他
  type n = number;
  type s = string;
  let num: n = 100;
  let str: s = "hell ts";
}
